Ralackk: I ordered a blu ray from zavvi recently (part of The Hut chain I believe) and the package was open when it arrived. So I was not best pleased and won't be using them again. Luckily the blu ray seemed fine otherwise.
F1ach: Sometimes a postal service opens mail, looking for contraband (happened to me a few times) and never seal the freaking stuff, which is bloody annoying. I cant imagine a retail outlet posting something in an opened condition tbh.
But when it's opened by the postal service or customs, aren't they supposed to (a) add a label to the packaging informing you they did this and (b) seal it back up again.
I've had a few packages opened by Japanese customs/UK customs and each time, they've added a label and resealed the package. I've had one note by the Japanese postal service explaining they had to reseal a package once (as whoever sent it, hadn't sealed it very well).
But then again, I've also had a package sent by Amazon UK that arrived in an open state (and those don't go via the Japanese postal service). I complained about it, and they sent a replacement copy of the item I'd ordered.